The following is a question submitted by DPTnT reader Daemon via our contact form.

Hi Max

I’m hoping you can help me understand some behavior I’ve been experiencing with my D700 and a couple of older flashes.

I’ve been hacking away with some older flashes; an SB-28DX and an SB-26, mounted together in a homemade bracket, and sync’ed together with an (I think) AS-10 cord. I can put an SB-800 on camera, trigger the two older flashes with a Pocket Wizard in the PC sync of one of the flashes, and the Pocket Wizard transmitter in the PC sync socket of the camera. If I keep the older flashes in full manual dump, I can get usable flash illumination at very high shutter speeds. I haven’t found a way to make this gear useful in the field, though. Too many variables and too much setup time. Also, there’s no way to vary the flash output, except for ND filters over the flash heads or some kind of physical obstruction of the amount of light that’s put out. I can send example images if you’d like.

My main question is: why does this work? What is it that the SB-800 does to my camera (D700) that allows it to incorporate the flash exposure from the two older units into the high-speed camera exposure? Without the SB-800 attached, the light from the older flashes will simply have no effect on the camera’s exposure. I’ll see the flashes go off, but they evidently are triggered too late to have any effect on the D700’s exposure. Do you see any way to answer that question?

Thanks, Daemon

Daemon,

Thanks for contacting us. Your question can be answered by our previous article titled High Speed Sync. If you have further questions, please feel free to contact us.